cp's OEIS Frontend

A079542 Triangular array: T(n,1) = T(n,n) = n and T(n,k) = lcm(T(n-1,k-1), T(n-1,k)) for 1 < k < n.

%I A079542 #11 Apr 25 2018 13:58:07
%S A079542 1,2,2,3,2,3,4,6,6,4,5,12,6,12,5,6,60,12,12,60,6,7,60,60,12,60,60,7,8,
%T A079542 420,60,60,60,60,420,8,9,840,420,60,60,60,420,840,9,10,2520,840,420,
%U A079542 60,60,420,840,2520,10,11,2520,2520,840,420,60,420,840,2520,2520,11,12
%N A079542 Triangular array: T(n,1) = T(n,n) = n and T(n,k) = lcm(T(n-1,k-1), T(n-1,k)) for 1 < k < n.
%C A079542 T(2*n-1,n) = A058312(n-1) for n <= 13.
%e A079542 Triangle begins:
%e A079542   1
%e A079542   2  2
%e A079542   3  2  3
%e A079542   4  6  6  4
%e A079542   5 12  6 12  5
%e A079542   6 60 12 12 60  6
%e A079542   7 60 60 12 60 60  7
%o A079542 (PARI) T(n,k) = if ((k==1) || (k==n), n, lcm(T(n-1,k-1), T(n-1,k)));
%o A079542 tabl(nn) = for (n=1, nn, for (k=1, n, print1(T(n,k), ", ")); print); \\ _Michel Marcus_, Apr 25 2018
%Y A079542 Cf. A080046.
%Y A079542 T(n, 2) = A003418(n-1) for n > 2.
%K A079542 nonn,tabl
%O A079542 1,2
%A A079542 _Reinhard Zumkeller_, Jan 22 2003